Long non-coding RNA XLOC_008466 acts as an oncogenic molecular in cervical cancer tumorigenesis

Long non-coding RNAs as critical regulators and novel targets in cervical cancer: current status and future perspectives

Cervical cancer is among the leading causes of cancer-associated mortality in women. In spite of vaccine availability, improved screening procedures, and chemoradiation therapy, cervical cancer remains the most commonly diagnosed cancer in 23 countries and the leading cause of cancer deaths in 36 countries. There is, therefore, a need to come up with novel diagnostic and therapeutic targets. Long non-coding RNAs (lncRNAs) play a remarkable role in genome regulation and contribute significantly to several developmental and disease pathways. The deregulation of lncRNAs is often observed in cancer patients, where they are shown to affect multiple cellular processes, including cell cycle, apoptosis, angiogenesis, and invasion. Many lncRNAs are found to be involved in the pathogenesis as well as progression of cervical cancer and have shown potency to track metastatic events. This review provides an overview of lncRNA mediated regulation of cervical carcinogenesis and highlights their potential as diagnostic and prognostic biomarkers as well as therapeutic targets for cervical cancer. In addition, it also discusses the challenges associated with the clinical implication of lncRNAs in cervical cancer.

Long Noncoding XLOC_006390 Regulates the Proliferation and Metastasis of Human Colorectal Cancer via miR-296/ONECUT2 Axis

Long noncoding RNA (LncRNA) XLOC_006390 has been shown to be dysregulated in cancer tissues and regulates cancer growth and development. Nonetheless, the molecular role of lncRNA-XLOC_006390 in colorectal cancer via modulation of miR-296/ONECUT2 axis is still unclear. Against this backdrop, the current study was designed to explore the role of lncRNA-XLOC_006390 in colorectal cancer proliferation and metastasis. The results revealed significant ( $P<0.05$ ) overexpression of lncRNA-XLOC_006390 in colorectal cancer tissues and cell lines, and the transcript levels increased with the advancement of the disease. Moreover, its high expression was shown to be associated with poor patient survival. Silencing of lncRNA-XLOC_006390 in colorectal cancer cells significantly ( $P<0.05$ ) suppressed their viability via onset of apoptosis and restricted cancer cell migration and invasion. In vivo tumor growth was significantly ( $P<0.05$ ) inhibited under lncRNA-XLOC_006390 repression. LncRNA-XLOC_006390 was shown to sponge the expression of miR-296-3p which in turn acted via post-transcriptional suppression of ONECUT 2 transcription factor to regulate the growth of colorectal cancer. Taken together, the results revealed the oncogenic role of lncRNA-XLOC_006390 in colorectal cancer via modulation of miR-296/ONECUT2 axis. The results also point towards its prognostic and therapeutic potential in the treatment of colorectal cancer.

LINC01354/microRNA-216b/KRAS Axis Promotes the Occurrence and Metastasis of Endometrial Cancer

OBJECTIVE

LINC01354 has been defined as a tumor driver in several cancers. Nevertheless, whether LINC01354 involves in endometrial cancer (EC) has been little navigated. Thus, the mechanism of LINC01354 was explored in the disease.

METHODS

Measurements of LINC01354, microRNA (miR)-216b and kirsten rat sarcoma viral oncogene (KRAS) levels in EC tissues and cells were performed. LINC01354 low expression and miR-216b overexpression vectors were introduced into EC cells (lshikawa), thereby their effects on cell viability, apoptosis, migration and invasion were manifested. Rescue experiments were also carried out by down-regulating LINC01354 and miR-216b spontaneously. Tumorigenesis in vivo was also assessed. The relationships of LINC01354/miR-216b/KRAS were analyzed.

RESULTS

Increased LINC01354 and KRAS and reduced miR-216b levels were measured in EC. Silencing LINC01354 or overexpressing miR-216b retarded EC cellular development. LINC01354 counteracted with miR-216b to target KRAS. Suppression of miR-216b antagonized silenced LINC01354-induced impacts on EC cell development. LINC01354/miR-216b/KRAS axis enhanced tumorigenesis in mice with EC.

CONCLUSION

It is testified that silencing LINC01354 inhibits KRAS by up-regulating miR-216b, thereby discouraging cell malignant phenotype in EC.

LncRNA MIR31HG is activated by STAT1 and facilitates glioblastoma cell growth via Wnt/β-catenin signaling pathway

Long non-coding RNAs (lncRNAs) have been reported to biologically regulate tumor progression. LncRNA MIR31HG has been identified as an oncogene in several cancer types, but its role and mechanism in glioblastoma (GBM) remain to be explored. In the present study, we detected strongly-expressed MIR31HG in GBM cells through RT-qPCR analysis. Through loss-of-function assays, we uncovered that MIR31HG exerted its oncogenic property in GBM through boosting cell proliferation and suppressing the apoptosis. Mechanistically, STAT1 was found to be as a transcription factor and played a part in activating the transcription of MIR31HG with upregulating the expression of MIR31HG in GBM. Moreover, high MIR31HG level was confirmed to induce the activation of Wnt/β-catenin signaling pathway in a variety of cancers. From subcellular fractionation and western blot assays, it was displayed that MIR31HG activated Wnt/β-catenin signaling pathway through enhancing the nuclear translocation of β-catenin. Rescue assays showed that the treatment of LiCl countervailed MIR31HG depletion-induced inhibition on GBM cell growth. In conclusion, STAT1-induced upregulation of lncRNA MIR31HG facilitates GBM cell growth by activating Wnt/β-catenin signaling pathway.

Long noncoding RNAs (lncRNAs) in cervical carcinogenesis: New molecular targets, current prospects

Aberrant expression of lncRNAs has been seen as a key factor in a wide range of diseases including cancer. The role of lncRNAs in cervical cancer has not been clearly explained, and has been the subject of recent studies. In this review, we have compiled an updated list of previously reported lncRNAs and established a general profile of these transcripts in accordance with the role they play in cervical carcinogenesis. Thus, information here includes the influence of lncRNAs on cervical tumorigenic process through a disturbance of cellular activities. Additionally, we described recent discoveries about how HPV contributes to lncRNAs expression in cervical cancer and we summarized exploratory studies of strategies adopted to modulate the expression levels of lncRNAs to treat cervical neoplasia, by drawing attention to radio and chemo-resistance. Finally, this paper provides a broad overview that sets out new research directions about the role of lncRNAs in cervical cancer.

LINC01410 Knockdown Suppresses Cervical Cancer Growth and Invasion via Targeting miR-2467-3p/VOPP1 Axis

Background

Long noncoding RNAs have essential roles in human diseases, including cancer. Our work aims to assess the function and mechanisms of LINC01410 in cervical cancer (CC) development.

Methods

Expression analyses were performed using qRT-PCR. Proliferation was determined through CCK8 and colony formation assays. Cell migration and invasion were determined by Transwell assay. The interactions among LINC01410, miR-2467-3p and VOPP1 were analyzed via luciferase reporter assay.

Results

LINC01410 was upregulated in CC tissues and cell lines. LINC01410 upregulation correlated with poor prognosis. LINC01410 silencing suppressed proliferation, migration and invasion of CC cells. LINC01410 was the sponge for miR-2467. And LINC01410 promoted VOPP1 expression through inhibiting miR-2467.

Conclusion

Our findings demonstrated that LINC01410 contributed to CC progression through regulating miR-2467/VOPP1 axis and suggested that LINC01410/miR-2467/VOPP1 cascade may be a potential therapeutic target.

LINC00116 enhances cervical cancer tumorigenesis through miR-106a/c-Jun pathway

Some studies imply that LINC00116 is involved in cervical cancer progression; however, the molecular mechanism by which LINC00116 modulating tumorigenesis of cervical cancer remains not clear. Reverse transcription-quantitative PCR (RT-qPCR) and the Western blot approaches were employed to probe genes expression levels. To examine the tumorigenic abilities of cervical cancer cells, MTT assay, Transwell assay, and wound-healing assay were used to investigate proliferation, invasion, and migration of HeLa or C-33A cells. LINC00116 knockdown attenuates cell proliferation, invasion, and migration of cervical cancer cells. miR-106a directly binds LINC00116 and regulate each other. Moreover, miR-106a inhibitor remarkably enhanced tumorigenesis of shLINC00116 HeLa cells. Through bioinformatic and dual-luciferase reporter assay, the results showed that miR-106a mimic directly targeted and downregulated the c-Jun. c-Jun overexpression could greatly rescue miR-106a mimic-modulated cervical cancer tumorigenesis. LINC00116 knockdown and miR-106a mimic-modulated programmed cell death ligand 1 (PD-L1) expression, which could be reverted by c-Jun introduction. LINC00116, PD-L1, and JUN were both upregulated in cervical cancer tumors compared to normal tissues. Lower expression levels of LINC00116 and JUN, as well as higher level of miR-106a were closely associated with higher overall survival of cervical cancer patients. Here, we report a novel role for LINC00116 in tumorigenesis of cervical cancer by regulating miR-106a/c-Jun axis. Our findings provide a foundation for understanding cervical cancer and facilitate the development of therapeutical approaches by targeting LINC00116.

SP1-mediated long noncoding RNA POU3F3 accelerates the cervical cancer through miR-127-5p/FOXD1

Emerging evidence supports the critical roles of long noncoding RNA (lncRNA) in cervical cancer. However, the pathological roles of lncRNA POU3 F3 in the cervical cancer tumorigenesis are still elusive. POU3 F3 was validated to be up-regulated in the cervical cancer tissue specimens and cells comparing with normal controls. Moreover, the ectopic overexpression of POU3 F3 was closely correlated with poor prognosis. In vitro, POU3 F3 promoted the proliferation, invasion of cervical cancer cells. In vivo, POU3 F3 knockdown repressed the tumor growth of cervical cancer cells. The transcriptional expression of POU3 F3 was activated by the transcription factor SP1. Mechanically, POU3 F3 acted as the sponge to target miR-127-5p, while miR-127-5p bind with the 3'-UTR of FOXD1 gene. In conclusion, our data verifies that lncRNA POU3 F3, induced by transcription factor SP1, acts as an oncogene in the cervical cancer tumorigenesis via regulating miR-127-5p/FOXD1 axis, providing a possible therapeutic target for cervical cancer.

Role of Long Noncoding RNA 799 in the Metastasis of Cervical Cancer through Upregulation of TBL1XR1 Expression

Long noncoding RNAs (lncRNAs) are closely associated with the molecular mechanisms underlying cancer development, and it would be highly useful to study their expression and mechanisms in cervical cancer too. The current study investigated lncRNA799 expression in cervical cancer in order to determine its clinical importance in the progression of cervical cancer. lncRNA799 expression was studied in 218 cervical cancer samples. Expression of lncRNA799 was significantly higher in the cervical cancer tissue than in the adjacent normal tissue. Overexpression of lncRNA799 was found to have a significant correlation with FIGO stage, SCC-Ag level, and lymphatic metastasis, and it was also associated with poor survival. Ectopic expression of lncRNA799 promoted the metastasis of SiHa cells, whereas lncRNA799 knockdown had an inhibitory effect on metastasis. Western blot analysis demonstrated that lncRNA799 promotes the expression of transducing β-like protein 1-related protein (TBL1XR1), and that lncRNA799 and TBL1XR1 expression show strong correlation in cervical cancer. Moreover, lncRNA799 modulated the expression of TBL1XR1 by acting as a competitive endogenous RNA (ceRNA) for miR-454-3P. The results indicate that lncRNA799 could be used as a novel marker of cervical cancer prognosis. Thus, targeting the ceRNA network involving lncRNA799 could be a potential treatment strategy against cervical cancer.

LncRNA DGCR5 represses the development of hepatocellular carcinoma by targeting the miR-346/KLF14 axis

Long non-coding RNAs (lncRNAs) are a class of regulatory noncoding RNAs. Emerging evidence highlights the critical roles of lncRNAs in the progression of hepatocellular carcinoma (HCC). Although many lncRNAs have been identified in the development of HCC, the association between DiGeorge syndrome critical region gene 5 (DGCR5) and HCC remains unclear. In the current study, we focused on the biological role of DGCR5 in HCC. We observed that DGCR5 was decreased in HCC cells, including SMCC7721, Hep3B, HepG2, MHCC-97L, MHCC-97H, and SNU449 hepatocellular carcinoma cells, compared with the normal human liver cell line THLE-3 normal human liver cells. In addition, DGCR5 overexpression could repress HCC cell growth, migration, and invasion considerably. Increasing studies have indicated the interactions between lncRNAs and microRNAs. MicroRNAs are endogenous small noncoding RNAs and they can play important roles in tumorigenesis. MicroRNA 346 (miR-346) has been demonstrated in various human cancer types, including HCC. MiR-346 was found to be increased in HCC cells and DGCR5 can act as a sponge of miR-346 to modulate the progression of HCC. The binding correlation between DGCR5 and miR-346 was validated in our research. Subsequently, Krüppel-like factor 14 (KLF14) was predicted as a downstream target of miR-346 and miR-346 can induce the development of HCC by inhibiting KLF14. Finally, we proved that DGCR5 can rescue the inhibited levels of KLF14 repressed by miR-346 mimics in MHCC-97H and Hep3B cells. Taken together, it was indicated in our study that DGCR5 can restrain the progression of HCC through sponging miR-346 and modulating KLF14 in vitro.

Downregulation of microRNA-216b contributes to glioma cell growth and migration by promoting AEG-1-mediated signaling

Accumulating evidence indicates microRNA-216b (miR-216b) plays an important role in the development and progression of various cancers. However, little is known about the function of miR-216b in gliomas. In this study, we aimed to investigate the expression level and functional significance of miR-216b in gliomas. We found that miR-216b was significantly downregulated in glioma specimens and cell lines. Overexpression of miR-216b suppressed the growth and migration of glioma cells, while miR-216b inhibition showed the opposite effects. Astrocyte elevated gene-1 (AEG-1) was predicted as a potential target gene of miR-216b by bioinformatics analysis. A dual-luciferase reporter assay showed that miR-216b could directly target the 3'-untranslated region of AEG-1. RT-qPCR and western blot analysis showed that miR-216 negatively regulated AEG-1 expression in glioma cells. Correlation analysis revealed an inverse correlation between miR-216b and AEG-1 in clinical glioma specimens. miR-216b also regulated the activation of nuclear factor-κB and Wnt signaling in glioma cells. Moreover, restoration of AEG-1 expression partially reversed the inhibitory effect of miR-216b overexpression on glioma cell growth and migration. Overall, these results revealed a tumor suppressive role of miR-216b in glioma tumorigenesis, and identified AEG-1 as a target gene of miR-216b action. Our study suggests that miR-216b can be potentially targeted for the development of novel therapies for gliomas.

Up-regulated BCAR4 contributes to proliferation and migration of cervical cancer cells

OBJECTIVES

Recently, thousands of long non-coding RNAs (lncRNAs) involved in development and metastasis of malignant tumors have been identified. Long non-coding RNA (lncRNA) breast cancer anti-estrogen resistance 4 (BCAR4) has been proved to promote proliferation and metastasis in multiple tumors. However, the function and significance of BCAR4 in cervical cancer are still unclear.

METHODS

In this study, we concentrated on the biological function and clinical significance of BCAR4 in cervical cancer. More specifically, BCAR4 expression was evaluated in cervical cancer tissues and cell lines by qRT-PCR. Moreover, the prognostic factors were assessed by Kaplan-Meier analysis and Cox proportional hazards models. Additionally, functional assays were conducted and the potential mechanism was explored.

RESULTS

Our study showed that BCAR4 expression was significantly up-regulated in cervical cancer tissue and cell lines. Moreover, patients with high BCAR4 expression showed worse survival outcomes and overexpression of BCAR4 might be an independent prognostic factor in cervical cancer. Furthermore, overexpression of BCAR4 remarkably promoted the proliferation, motility of cervical cancer cells and silencing BCAR4 significantly suppressed the proliferation, migration and invasion of cervical cancer cells. Additionally, overexpression of BCAR4 promoted epithelial-mesenchymal transition (EMT) process and silencing BCAR4 suppressed EMT process in cervical cancer cells.

CONCLUSIONS

The results indicated that BCAR4 might play a crucial role in cervical cancer progression and act as an underlying biomarker for the diagnosis and prognosis of cervical cancer.